Liquid crystal display devices, which are display devices that use liquid crystal compositions for display, typically adopt display systems in which a liquid crystal panel including a pair of substrates between which a liquid crystal composition is filled is irradiated with light from a backlight, and a voltage is applied to the liquid crystal composition to change the alignment of liquid crystal molecules, thereby controlling the amount of light that can be transmitted through the liquid crystal panel. Such liquid crystal display devices are characterized by being thin and light and consuming little electricity, and thus have been used in electronic devices such as smartphones, tablet PCs, and car navigation systems.
Particularly in applications such as smartphones and tablet PCs, where the sizes of bodies are limited, it has been necessary to narrow off-screen areas to achieve larger screens. Thus, liquid crystal display devices are required to include liquid crystal panels having peripheries (hereinafter also referred to as “frames”) with reduced widths.
In applications such as smartphones, pixels have recently been achieving a high resolution. This tends to increase the number and area of wires and black matrices in liquid crystal panels to decrease the ratio of the area of apertures that can be used for display (aperture ratio). Decreases in aperture ratio are directly linked to decreases in the amount of light that can be transmitted through liquid crystal panels. Thus, to maintain the display performance, such as contrast ratio, of liquid crystal display devices, studies have been conducted to significantly improve the luminance of backlights.
Liquid crystal compositions for use in liquid crystal display devices have been required to have improved stability so as to withstand loads during the process for manufacturing the liquid crystal display devices and such that the liquid crystal display devices manufactured can exhibit stable properties over a long period of time. For example, Patent Literature 1 discloses the addition of an antioxidant and a light stabilizer to a liquid crystal composition. Patent Literature 2 discloses the addition of a stabilizer to a liquid crystal composition (see Table C at paragraphs [0208] to [0211]).